So you recently had sex. Now, something doesn’t feel quite right. If you’re itching, hurting, or sore, you could have a sexually transmitted infection (STI). For your sexual health — and your partner’s — you need to find out for sure.

If you’re sexually active, you’re potentially at risk. STIs are extremely common. In fact, according to the CDC, there are 20 million new cases annually. That means getting an STI is nothing to be embarrassed about. It also means you should get tested and start treatment to prevent spreading it to others.

Some STIs are tricky and don’t cause symptoms. You can have them and not even know. If you’ve had unprotected sex — or think you’re at risk — take a test or talk to your doctor. Seek help if you’re experiencing any of these eight symptoms.

1. Painful Sex

Under most circumstances, sex should feel good. If it doesn’t, pay attention. Pain during sex is common with many STIs such as gonorrhea, chlamydia, herpes, syphilis, and trichomoniasis. 

Consider at-home STI testing if playtime between the sheets, including attempted penetration, hurts or burns. For men, a painful stinging sensation during ejaculation is a warning sign. See your doctor for treatment if your at-home test comes back positive.

2. Blisters and Sores

Blisters, fluid-filled pimples, and itchy white bumps around your genitals are frequently a tell-tale STI sign. They’re common with some of the most contagious STIs like genital herpes and syphilis. Syphilis is curable. Herpes isn’t, but you can keep outbreaks at bay (and reduce transmission risk) by following a treatment plan.

These types of sores also show up with human papillomavirus (HPV). Additionally, if you’ve been exposed to HPV via oral sex, painful sores can develop around your mouth.

3. Unusual, Unpleasant Discharge

Overall, vaginal discharge is normal and healthy. When it looks — and smells — different, though, ask questions. This is particularly true if you see blood when it’s not time for your period. Abnormal bleeding is always cause for concern. For men, any type of discharge should prompt a visit to the doctor. 

If your discharge is yellow or green with a strong, fishy odor, get tested. Multiple STIs including trichomoniasis, chlamydia, and gonorrhea could be responsible.

Not all discharge points to an STI, however. White discharge that resembles cottage cheese could be a yeast infection. Regardless, if your vaginal discharge is suddenly different, make that doctor’s appointment.

4. Rash

A skin rash that suddenly appears can be confusing. Is it an STI symptom or a sign of another health condition like diabetes or an allergy? You’ll need a doctor to know for sure.

Keep in mind, though, rashes are common with several STIs, including syphilis, chlamydia, gonorrhea, and scabies. A brown or red rash pops up on the palms of your hands or soles of your feet with syphilis. A chlamydia, gonorrhea, or scabies rash is red and splotchy. Most are painless, and they appear in a pattern. Rashes on your genitals are almost always connected to an infection. 

5. Painful Peeing

A trip to the bathroom shouldn’t be painful. If it hurts or burns to pee, you could have an STI. It’s a symptom that can emerge no matter what STI you have. Bacterial (chlamydia or gonorrhea), parasitic (trichomoniasis), or viral STIs (genital herpes) can all make you dread a pitstop. 

Don’t jump to conclusions if a moment of restroom relief is uncomfortable. STIs aren’t the only cause. Other types of infections — yeast, penile, or urinary tract — could be the culprit. You’ll need a test to figure it out, so make an appointment with your doctor.

6. Pelvic Pain

Speaking of pain, STIs can make your entire pelvis or abdomen hurt. It’s uncommon, but it’s possible, especially with gonorrhea and trichomoniasis. When it happens, pain can be severe.

Treatment is critical because these infections can spread to the uterus or abdomen, causing pelvic inflammatory disease (PID) in women. Left untreated, PID can lead to infertility or (rarely) death. Simply put, talk to your doctor about pelvic pain.

7. Swollen Lymph Nodes

Your lymph nodes, located in your neck, arm pits, and groin, are a big part of your immune system. When they’re inflamed, your first thought could be the flu or strep throat. As it turns out, STIs can also cause these glands to swell.

Abscessed teeth, ear infections, or other viruses can trigger swollen glands that feel like marbles, too. If you think you’re at risk for an STI, though, get tested. Your doctor can pinpoint the underlying problem and give you the right treatment.

8. Itching “Down There”

An occasional genital itch-and-scratch is no big deal. If it’s infrequent, don’t worry. When you’re squirming from a constant, intense distraction, however, don’t ignore it. Trichomoniasis or herpes could be to blame. 

STIs aren’t the only cause for itchy pubic regions, though. It could be a dermatological condition you need to address. Yeast infections are also notorious for prompting a nearly constant itching sensation. Make a doctor’s appointment to find out for sure. 

Getting treated for STIs is vital for your sexual health. It can be hard to do, though, because you may never have symptoms. Or, when you do, they could point to other health problems. Getting tested every now and then is a good idea. Be sure you use a condom every time you have sex, too. It’s the only contraceptive method that can prevent STIs.

If you know you’ve been exposed or just think you have, make an appointment with your doctor. Getting tested can put your mind at ease or get you the treatment you need to protect you and your partner.